公共出版物能够提供大量有用的信息，包括（）。
A.行业年鉴
B.统计报告
C.调查报告
D.气象资料
E.问卷调查
参考答案：A, B, C
-What do you think of maths?
-My favourite. It's ________ for me to study of all the subjects in school.[ ]
A. more difficult
B. the most difficult
C. less difficult
D. the least difficult
有机物对金属无腐蚀作用。
